Hydroxychloroquine or chloroquine +/- azithromycin: heart disorders

In patients with COVID-19 infection, treatment with hydroxychloroquine (HQC) or chloroquine (CQ) alone or in combination with azithromycin increases the risk of serious heart disorders, according to findings of a study published Drugs - Real World Outcomes.

Data from the US FDA Adverse Event Reporting System (FAERS) in 2020 were used to investigate the risk of serious cardiovascular adverse events (SCAEs; composite of cardiac arrest, ventricular arrhythmia, atrial fibrillation, bradyarrhythmia, rate-correct QT [QTc] interval prolongation, myocardial infarction, stroke, heart failure, coronary ischaemia and torsade de pointes [TdP]) in patients with COVID-19 infection receiving HCQ or CQ alone or in combination with azithromycin.

Treatment with HCQ or CQ was associated with significantly increased reporting of SCAEs (reporting odds ratio [ROR] 2.1; 95% CI 1.8, 2.5), TdP or QTc interval prolongation (ROR 35.4; 95% CI 19.4, 64.5) and ventricular arrhythmia (ROR 2.5; 95% CI 1.6, 3.9) compared with remdesivir. HCQ or CQ was also associated with significantly increased reporting of ventricular arrhythmia (ROR 10.5; 95% CI 3.3, 33.4) compared with lopinavir/rotinavir. RORs were higher in patients receiving HCQ or CQ or in combination with azithromycin.

In 2020, reports of SCAEs with use of HCQ or CQ and azithromycin included QTc prolongation (61.4%), ventricular arrhythmia (12.0%), atrial fibrillation (8.2%), TdP (4.9%), and cardiac arrest (4.4%); 13.7% of cases resulted in death.

"Given the scarcity of evidence demonstrating benefits from HCQ/CQ treatment for patients with COVID-19, the evidence for harm is crucial for clinical decision making. Together with prior evidence, our data provide further evidence to caution against the widespread use of the combination regimen in preventing or treating COVID-19, especially in vulnerable populations," said the authors.